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1.
R. P. Heaney T. M. Zizic I. Fogelman W. P. Olszynski P. Geusens C. Kasibhatla N. Alsayed G. Isaia M. W. Davie C. H. Chesnut III 《Osteoporosis international》2002,13(6):501-505
Risedronate treatment reduces the risk of vertebral fracture in women with existing vertebral fractures, but its efficacy
in prevention of the first vertebral fracture in women with osteoporosis but without vertebral fractures has not been determined.
We examined the risk of first vertebral fracture in postmenopausal women who were enrolled in four placebo-controlled clinical
trials of risedronate and who had low lumbar spine bone mineral density (BMD) (mean T-score =–3.3) and no vertebral fractures at baseline. Subjects received risedronate 5 mg (n= 328) or placebo (n= 312) daily for up to 3 years; all subjects were given calcium (1000 mg daily), as well as vitamin D supplementation (up
to 500 IU daily) if baseline serum 25-hydroxyvitamin D levels were low. The incidence of first vertebral fracture was 9.4%
in the women treated with placebo and 2.6% in those treated with risedronate 5 mg (risk reduction of 75%, 95% confidence interval
37% to 90%; P= 0.002). The number of patients who would need to be treated to prevent one new vertebral fracture is 15. When subjects were
stratified by age, similar significant reductions were observed in patients with a mean age of 64 years (risk reduction of
70%, 95% CI 8% to 90%; P= 0.030) and in those with a mean age of 76 years (risk reduction of 80%, 95% CI 7% to 96%; P= 0.024). Risedronate treatment therefore significantly reduces the risk of first vertebral fracture in postmenopausal women
with osteoporosis, with a similar magnitude of effect early and late after the menopause.
Received: 12 September 2001 / Accepted: 11 December 2001 相似文献
2.
Alzheimer’s disease (AD) is the most common cause of dementia affecting nearly 18 million people around the world and 4.5 million in the US. It is a progressive neurodegenerative condition that is estimated to dramatically increase in prevalence as the elderly population continues to grow. As the cognitive and neuropsychiatric signs and symptoms of AD progresses in severity over time, affected individuals become increasingly dependent on others for assistance in performing all activities of daily living. The burden of caring for someone affected by the disorder is great and has substantial impact on a family’s emotional, social and financial well-being. In the US, the currently approved medications for the treatment of mild to moderate stages of AD are the cholinesterase inhibitors (ChEIs). Cholinesterase inhibitors have shown modest efficacy in terms of symptomatic improvement and stabilization for periods generally ranging from 6 to 12 months. There are additional data that have emerged, which suggest longer-term benefits. For the moderate to severe stages of AD, memantine, an N-methyl-D-aspartate (NMDA) receptor antagonist is in widespread use and has shown modest benefit as monotherapy and in combination with ChEIs. The cost effectiveness of the currently available therapeutic agents for AD has undergone great scrutiny and remains controversial, especially outside the US. Neuropsychiatric symptoms such as agitation and psychosis are common in AD. Unfortunately, in the US there are no Food and Drug Administration (FDA)-approved agents for the treatment of these symptoms, although atypical antipsychotics have shown some efficacy and have been widely used. However, the use of these agents has recently warranted special caution due to reports of associated adverse effects such as weight gain, hyperlipidemia, glucose intolerance, cerebrovascular events, and an increased risk for death. Alternative agents used to treat neuropsychiatric symptoms include serotonergic antidepressants, benzodiazepines, and anticonvulsant medications. 相似文献
3.
Konstantin Musiychuk Natalie Stephenson Hong Bi Christine E. Farrance Goran Orozovic Maria Brodelius Peter Brodelius April Horsey Natalia Ugulava Abdel‐Moneim Shamloul Vadim Mett Shailaja Rabindran Stephen J. Streatfield Vidadi Yusibov 《Influenza and other respiratory viruses》2007,1(1):19-25
Historically, most vaccines have been based on killed or live‐attenuated infectious agents. Although very successful at immunizing populations against disease, both approaches raise safety concerns and often have limited production capacity. This has resulted in increased emphasis on the development of subunit vaccines. Several recombinant systems have been considered for subunit vaccine manufacture, including plants, which offer advantages both in cost and in scale of production. We have developed a plant expression system utilizing a ‘launch vector’, which combines the advantageous features of standard agrobacterial binary plasmids and plant viral vectors, to achieve high‐level target antigen expression in plants. As an additional feature, to aid in target expression, stability and purification, we have engineered a thermostable carrier molecule to which antigens are fused. We have applied this launch vector/carrier system to engineer and express target antigens from various pathogens, including, influenza A/Vietnam/04 (H5N1) virus. 相似文献
4.
G. R. van der Werf J. Dempewolf S. N. Trigg J. T. Randerson P. S. Kasibhatla L. Giglio D. Murdiyarso W. Peters D. C. Morton G. J. Collatz A. J. Dolman R. S. DeFries 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(51):20350-20355
Drainage of peatlands and deforestation have led to large-scale fires in equatorial Asia, affecting regional air quality and global concentrations of greenhouse gases. Here we used several sources of satellite data with biogeochemical and atmospheric modeling to better understand and constrain fire emissions from Indonesia, Malaysia, and Papua New Guinea during 2000–2006. We found that average fire emissions from this region [128 ± 51 (1σ) Tg carbon (C) year−1, T = 1012] were comparable to fossil fuel emissions. In Borneo, carbon emissions from fires were highly variable, fluxes during the moderate 2006 El Niño more than 30 times greater than those during the 2000 La Niña (and with a 2000–2006 mean of 74 ± 33 Tg C yr−1). Higher rates of forest loss and larger areas of peatland becoming vulnerable to fire in drought years caused a strong nonlinear relation between drought and fire emissions in southern Borneo. Fire emissions from Sumatra showed a positive linear trend, increasing at a rate of 8 Tg C year−2 (approximately doubling during 2000–2006). These results highlight the importance of including deforestation in future climate agreements. They also imply that land manager responses to expected shifts in tropical precipitation may critically determine the strength of climate–carbon cycle feedbacks during the 21st century. 相似文献
5.
Arati Mane Sunitha Manjari Kasibhatla Pallavi Vidhate Vandana Saxena Sandip Patil Amrita Rao Amit Nirmalkar Urmila Kulkarni-Kale Samiran Panda 《Emerging infectious diseases》2022,28(4):725
An HIV outbreak investigation during 2017–2018 in Unnao District, Uttar Pradesh, India, unearthed high prevalence of hepatitis C virus (HCV) antibodies among the study participants. We investigated these HCV infections by analyzing NS5B and core regions. We observed no correlation between HIV–HCV viral loads and clustering of HCV sequences, regardless of HIV serostatus. All HCV isolates belonged to genotype 3a. Monophyletic clustering of isolates in NS5B phylogeny indicates emergence of the outbreak from a single isolate or its closely related descendants. The nucleotide substitution rate for NS5B was 6 × 10−3 and for core was 2 × 10−3 substitutions/site/year. Estimated time to most recent common ancestor of these isolates was 2012, aligning with the timeline of this outbreak, which might be attributable to unsafe injection practices while seeking healthcare. HIV–HCV co-infection underlines the need for integrated testing, surveillance, strengthening of healthcare systems, community empowerment, and molecular analyses as pragmatic public health tools. 相似文献
6.
The purpose of this paper to identify the optimal therapy after radical prostatectomy (RP) for patients with adenocarcinoma of the prostate invading the seminal vesicles (pT3bN0M0 or SVI). A PubMed search using the keywords 'prostate', 'seminal vesicle', 'prostatectomy', 'radiotherapy', 'androgen blockade' was performed to identify literature regarding rates of disease failure in patients with SVI who are observed or treated with androgen blockade (AB), radiotherapy (RT) or RT + AB after RP. The outcome of 68 patients treated at Duke University with post-operative AB, RT or RT + AB for pT3bN0M0 is also presented. More than 70% of patients with SVI develop disease recurrence after surgery. For many, recurrence occurs within 2 y after RP. These patients have poor control rates with postoperative RT alone. While experience with AB and RT+AB is limited, control rates are generally superior to RT alone. At Duke University, after a median follow-up of nearly 4 y, patients treated with RT + AB or AB alone for pT3bN0M0 achieved better 5-y progression-free survival (PFS) compared with those who received RT alone (78 and 68 vs 30%, P = 0.03 and 0.046, respectively). There was no PFS difference between those who received AB alone or RT + AB (68 vs 78%, P=0.5). Seminal vesicle invasion confers a poor prognosis after RP. SVI is a consistent predictor of poor outcome after RT. The limited data available examining AB and RT + AB in pT3bN0M0 disease, including data from Duke University, are encouraging. Nonetheless, postoperative AB, RT and RT + AB for pT3bN0M0 disease require prospective evaluation, as RP alone is rarely curative. 相似文献
7.
Kemnitzer W Drewe J Jiang S Zhang H Wang Y Zhao J Jia S Herich J Labreque D Storer R Meerovitch K Bouffard D Rej R Denis R Blais C Lamothe S Attardo G Gourdeau H Tseng B Kasibhatla S Cai SX 《Journal of medicinal chemistry》2004,47(25):6299-6310
By applying a novel cell- and caspase-based HTS assay, 2-amino-3-cyano-7-(dimethylamino)-4-(3-methoxy-4,5-methylenedioxyphenyl)-4H-chromene (1a) has been identified as a potent apoptosis inducer. Compound 1a was found to induce nuclear fragmentation and PARP cleavage, as well as to arrest cells at the G(2)/M stage and to induce apoptosis as determined by the flow cytometry analysis assay in multiple human cell lines (e.g. Jurkat, T47D). Through structure-activity relationship (SAR) studies of the 4-aryl group, a 4- and 7-fold increase in potency was obtained from the screening hit 1a to the lead compounds 2-amino-4-(3-bromo-4,5-dimethoxyphenyl)-3-cyano-7-(dimethylamino)-4H-chromene (1c) and 2-amino-3-cyano-7-(dimethylamino)-4-(5-methyl-3-pyridyl)-4H-chromene (4e), with an EC(50) of 19 and 11 nM in the caspase activation assay in T47D breast cancer cells, respectively. The 2-amino-4-aryl-3-cyano-7-(dimethylamino)-4H-chromenes also were found to be highly active in the growth inhibition MTT assay, with GI(50) values in the low nanomolar range for compound 1c. Significantly, compound 1c was found to have a GI(50) value of 2 nM in the paclitaxel resistant, p-glycoprotein overexpressed, MES-SA/DX5 tumor cells. Functionally, compound 1c was found to be a potent inhibitor of tubulin polymerization and to effectively inhibit the binding of colchicine to tubulin. These results confirm that the cell-based caspase activation assay is a powerful tool for the discovery of potent apoptosis inducers and suggest that the 4-aryl-4H-chromenes have the potential to be developed into future anticancer agents. 相似文献
8.
9.
Present study was conducted to investigate the acute and sub-acute toxic effect of diplodiatoxin with special reference to biochemical membrane bound enzymes like aspartate aminotransferase (ASAT), alanine aminotransferase (ALAT) and RBC acetylcholinesterase (AChE) in male and female rats. For acute study, rats were treated with a single oral dose of 5.7 mg/kg of diplodiatoxin, whereas for sub-acute study, the rats received 0.27 mg/kg/day for 21 days. Acute and sub-acute diplodiatoxin treatment caused loss in body weight and feed intake along with symptoms including irritation, dullness, tremors and convulsions. Diplodiatoxin caused a significant increase in serum ASAT and ALAT and a decrease in activity in the liver in both acute and sub-acute studies. This compound also significantly inhibited RBC AChE. Sexual dimorphism was observed when male rats were compared with female rats (p < 0.05). The enzyme alterations observed in the affected enzymes recovered to the normal levels by day 7 post treatment (withdrawal study) in both acute and sub-acute treated rats. A negative correlation was observed with regard to these enzymes when serum was compared with liver. These enzyme profiles show increases in serum with parallel decrease in liver, indicating necrosis of liver. These results suggest that diplodiatoxin has potential to affect hepatic end-points. 相似文献
10.
Yang W Guastella J Huang JC Wang Y Zhang L Xue D Tran M Woodward R Kasibhatla S Tseng B Drewe J Cai SX 《British journal of pharmacology》2003,140(2):402-412
1. Caspases play a critical role in apoptosis, and are considered to be key targets for the design of cytoprotective drugs. As part of our antiapoptotic drug-discovery effort, we have synthesized and characterized Z-VD-fmk, MX1013, as a potent, irreversible dipeptide caspase inhibitor. 2. MX1013 inhibits caspases 1, 3, 6, 7, 8, and 9, with IC50 values ranging from 5 to 20 nm. MX1013 is selective for caspases, and is a poor inhibitor of noncaspase proteases, such as cathepsin B, calpain I, or Factor Xa (IC50 values >10 microm). 3. In several cell culture models of apoptosis, including caspase 3 processing, PARP cleavage, and DNA fragmentation, MX1013 is more active than tetrapeptide- and tripeptide-based caspase inhibitors, and blocked apoptosis at concentrations as low as 0.5 microm. 4. MX1013 is more aqueous soluble than tripeptide-based caspase inhibitors such as Z-VAD-fmk. 5. At a dose of 1 mg kg-1 i.v., MX1013 prevented liver damage and the lethality caused by Fas death receptor activation in the anti-Fas mouse-liver apoptosis model, a widely used model of liver failure. 6. At a dose of 20 mg kg-1 (i.v. bolus) followed by i.v. infusion for 6 or 12 h, MX1013 reduced cortical damage by approximately 50% in a model of brain ischemia/reperfusion injury. 7. At a dose of 20 mg kg-1 (i.v. bolus) followed by i.v. infusion for 12 h, MX1013 reduced heart damage by approximately 50% in a model of acute myocardial infarction. 8. Based on these studies, we conclude that MX1013, a dipeptide pan-caspase inhibitor, has a good combination of in vitro and in vivo properties. It has the ability to protect cells from a variety of apoptotic insults, and is systemically active in three animal models of apoptosis, including brain ischemia. 相似文献